I hadn’t been in the National Concert Hall in an age. The beauty of the building hits you as you cross towards it over Earlsfort Terrace, lit up as it is on this night fashioned from rain and gale. As a venue it’s a year or two away from its fortieth anniversary although the building was first erected for a world’s fair in 1865, which attracted over 950,000 visitors. The Gloaming are only up to seven nights in the venue so far, but they’re getting there. James Joyce and Flann O’Brien served time as undergrads here when it formed the main berth of UCD so it is right and proper that this historic edifice should house contemporary national artistic treasures tonight.

Trying to describe the music of The Gloaming is no easy task – hark at this fella, tripping over his own notebook, in vain attempt. It is traditional Irish music -  for how could it not be with Martin Hayes, who was an All-Ireland Fiddle champion when he was barely out of short trousers and was on the road with the Tulla Céilí Band before he could vote, and Iarla Ó Lionáird who was a Gael Linn recording artist and a member of Seán Ó Riada's choir Cór Chúil Aodha before he was a teenager - but just as Ó Riada managed to forge something as brand new as 'The Banks Of Sulán' or 'Seoladh na nGamhan' by bringing European influences to bear on the Irish tradition, so The Gloaming have stepped beyond any easy categorisation.

Take opener 'Méachan Rudai', an adaptation from the poet Liam Ó Muirthile, a friend of Ó Lionáird who passed away last year. The title translates as ‘The Weight Of Things’ and the lyrics speak of “The weight of the pair of us. Our weight together…your living weight. Your dead weight. The weight of words rising and falling between us.” It takes a voice like Ó Lionáird’s to carry the heaviness of a lyric like that, with all of life sown into it. To his right on the stage, Thomas Bartlett sits at the grand piano. He might have borrowed that cardigan from Robert Smith, he might be wearing eye shadow, he looks like he has stepped in from another world and, in a way, he has. His stance at the piano sometimes resembles a loosely controlled marionette as his fingers dance across the keys. It’s the combination of his contribution – minimalism, classicism but also indie and post rock – with the traditional rooting the others share that makes The Gloaming a genre unto themselves.

‘The Lobster’ emerges out of the preceding tune, incorporating elements of the reel ‘The Boy In The Gap’ which Hayes has worked before on The Blue Room, an album released by his Martin Hayes Quartet. When Caoimhín Ó Raghallaigh takes over halfway through, attacking his hardanger d'amore fiddle - a mutated adaptation of the traditional Norwegian instrument with extra strings - in an almost hoedownic fashion, casting a campfire like shadow behind him, it illustrates the difference between these two players. Hayes’ tone is of a purity that the most pernickety expert at De Beers could appreciate, while Ó Raghallaigh seeks out the extraneous elements and noises that other fiddlers seek to eliminate. It’s almost like watching a trad version of Television as they swop between the cleaner lines of Tom Verlaine to the slightly more distorted tone of Richard Lloyd. When the opening set ends the audience is almost caught in shock for a second before erupting into applause. Martin Hayes thanks us for coming, glad for the deep connection the sharing of this music brings as the band strive for feeling over technique. He’s right of course but it is their technical mastery, earned through a lifetime’s toil, that allows them to express such feeling.

Ó Lionáird takes us back to the end of the bardic tradition to a lyric from Eoghan Rua Mac an Bhaird, who sailed from Lough Swilly to La Coruña, Spain with Hugh O’Neill in September 1607, the exile that became known as The Flight Of The Earls, for ‘My Lady Who Has Found The Tomb Unattended’. Ó Raghallaigh then takes improvisational flight, like a swallow over a briar patch, the melody flying clear as the electronic manipulation curls in upon itself. He has constructed the code that alters the signal, introducing random elements and the edges of chaos to the sound. It is mesmerising. We are pulled back to Earth by Hayes’ return for snatches of ‘My Darling’s Asleep’ and ‘Patsy Geary’s’, a tune perhaps familiar from The Bothy Band, and then into ‘Dr O’Neill’ from the new album to finish out the second set.

The words of Liam Ó Muirthile resurface for ‘Áthas’ a poem composed while walking the Camino de Santiago pilgrimage to the cathedral of Santiago de Compostela in northwestern Spain, lines coming to him with "the beat of his stick and the rhythm of his feet". It is beautifully sung over the delicate background constructed by the piano and Dennis Cahill’s gently plucked guitar. ‘The Pink House’ starts with the melody from ‘O’Sullivan’s March’, slowed down to a stately pace from the version The Chieftains included in the movie Rob Roy. Long-time partners Cahill and Hayes carry ‘Fainleog’ from the first album, Cahill’s strongly rhythmic yet sensitive playing allowing Hayes room to work before the band seamlessly segue into ‘Samhradh Samhradh’, closing the listener’s eyes and setting them loose in the tune’s swirl and eddies.

The two sides of the band are shown again as Bartlett relates a tale of Martinis in the bath across the street in the Conrad before Ó Lionáird brings it back to the slightly less than five star environs of Hartigan’s and the Ha’penny Bridge Inn for dirty pints. It’s also appropriate in a way for The Gloaming to adapt the poetry of Seán Ó Ríordáin as he’s credited with incorporating European themes into Irish poetry just as they are doing with the music. ‘Reo’ is a dark lyric where a found frosted handkerchief calls to mind the kissing of a deceased coffined woman, but any melancholy it might engender is lifted by Hayes’ finishing performance on ‘The Old Road To Garry’ which goes into what as best as I can work out is the tune ‘Hughie Traver’s’. His playing ducks and dives and swoops and soars as he speeds up threatening to either take off completely or combust.

There was no way they were to be let finish it at that, and The Gloaming quickly return to the stage to settle out the affair with ‘The Song of The Glens’ which Bartlett starts off like some lost Bernard Hermann horror soundtrack before Ó Lionáird’s powerhouse almost a cappella performance plugs right back into the sean-nós tradition he sprang from. Bartlett switches to organ as they move into ‘The Rolling Wave’ and the evening closes with - and again I’m only speculating here - The Bothy Band’s ‘Music In The Glen’, Hayes shouting out instruction and grinning to all as they successfully make land at the tune’s end. The standing ovation goes on for a deserved duration.

I’ve been lucky in my life to have been present for some transforming performances and this was one of them, music that lifted you up to take you back and forth through time, from the bardic age up through modern Irish poetry and the revival of Irish traditional music that began in the sixties, and on into tomorrow. Hayes’ magisterial tone and playing are rooted in the tradition while Ó Raghallaigh’s openness takes the instrument somewhere else, Bartlett and Cahill’s sensitive bedrock the springboard for their flights of fancy, and Ó Lionáird’s voice shining out like a lighthouse in a storm, all combining to stir a tribal sort of pride that you weren’t even aware of beforehand, moving you to a state of joy, a state of Áthas.